because, it turns out, they are only halfway done tearing down and building the rest of the so- called presidio parkway project. right now, this is a temporary situation. you can see this new bridge, the old one right behind it with the original truck needs to be torn down. then they will build a twin bridge in its place alongside the other new one. at that point, traffic will no longer be crowded onto one bridge with movable median markers. >> currently while this bridge is carrying both directions of traffic there's not enough sight lines and merging distance. to put additional traffic on that southbound, there's just not enough room for cars to merge safely. >> reporter: it's not safe to ramp on right now with traffic going in both directions and it won't be ready until late 2015 when the entire project is complete. >> ultimately there will be another twin bridge built and three more tunnels and a whole new interchange. so there's a lot more that people will see in the coming months and the coming years. >> reporter: joe vazquez, cbs 5. >>> doing donuts on the 880. the sideshow that shut dow